This application relates to a fastening device for furnishing panels, particularly furniture panels.
In the art various devices are known (see, for example, Italian applications No. 21246 A/79, 22696 B/77 and 23782 A/77 of the same applicant) for interconnecting or joining a plurality of panels making up a piece of furniture, so that said piece of furniture can be repeatedly disassembled and reassembled. Said prior patents disclose devices which are of increasing safety and easiness in operation, each of which being designed to solve a particular problem. However, said devices have some inconvenient features or complexities in use; for instance, it is inconvenient that said devices are formed of a plurality of separated parts.
DE No. A-2,546,526 teaches a device for joining wooden panels, in which a spreadable leg fastening means is engaged on a fixed wedge and driven therealong for leg spreading. The use of a fixed wedge involves a relative complexity in manufacture; it further involves the necessity of making the wedge and a housing integral therewith of relatively high-quality materials, since not only a protective, but also a resistant function is assigned thereto, whereby the device is comparatively costly. Further, the device shown is not reversible, that is once clamped it cannot be unclamped. Finally, arm spreading or widening out can occur only to the predetermined extent corresponding to the wedge thickness.
FR No. A-2,152,941 shows a fastening device, particularly for sections or structural shapes, in which two hook-like elements are movable between an approached position, in which they do not effect any blocking, and a spread apart position at which they provide for section blocking. A separate spring element presses the hooks to a mutual approached position; a cam element is placed through the hook elements in holes drilled therein, and has a single cam portion which is eccentric with respect to the axis of rotation, this portion pulling said elements back; the spreading of the latter is provided by means of a fixed pin, against which the hook elements will impact when retracted from the cam. A disadvantage of this type of device is the relative complexity due to the number of parts to be assembled and the required accuracy in assembling, the whole involving a relatively high cost of the device. Further, the described device cannot be used for wooden panels, since the arrangement of the parts, providing that the widening out of the arms occurs in the same direction as the axis of rotation, is such as either to prevent the device handling or to split the panel in which the hook arms are engaged.
DE No. A-2,623,814 also teaches a fastening device for sections or structural shapes, comprising two arms which can be spread out by means of a cam. A wedge means is integral with the cam. Also in this case, the cam has an axis parallel to the direction in which such arms spread out and the device cannot be used on wooden panels; further, the assembling thereof is particularly complicated.
EP No. A-0,070,362 also teaches a connection means for section bars in which, as in the above cited publications, a cam cooperates with inclined plane surfaces to displace a fastening member between free and blocked position. Also in this case, for the above reasons set forth in connection with FR No. A-2,152,941 the connection device cannot be used for wooden panels, and further the requirement of prearranging a plurality of inclined planes in a relatively accurate array within the box of the device makes the latter quite costly to manufacture.